I've been struggling with this for a while, and now that I've finally achieved success, I wanted to report my results for anyone else to benefit from.

My mission was to get my PowerBook to drive my Sharp LC-37GD4U at its native resolution. There were three points to this objective: 1) Use the entire screen, 2) Have an unscaled (i.e. "perfect") image, and 3) have the entire image fit on the screen (i.e. no overscan).

The trouble comes from the fact that the native resolution of the panel is 1366x768, but that resolution is not presented as an option by OS X. An interesting side note is that you can connect your DVI output to the DVI input and also with the right cable, the HDMi input. The HDMI input allows a resolution of 1344x756 - very close to native, but no way to fine tune it. The HDMI image will be overscanned - too big for the screen by about an inch all the way around - and it will be scaled, so lots of images will look worse on it than they do on a computer display. The Sharp offers excellent fine tuning capabilities on the DVI input, but absolutely none on the HDMI input.

The DVI input offers 1280x768 - also very close to native, but far enough that it gets scaled. However, along the way I realized that if I set the view mode to "dot by dot" (instead of sidebar, zoom or stretch) - that it does not get scaled, and that with some fine tuning, you can align the signal with the panel for a perfect image. More on that below. But the point is I could have stopped here, having achieved a perfect image and use of 100% of the panel's vertical resolution, and 94% of it's horizontal resolution.

So keep in mind, if you continue here, all you are going to get, beyond going with 1280x768, dot by dot, and fine-tuning, is 86 more pixels. It is worth noting that with the same utility that I used, you could theoretically customize 1344x756 over the HDMI to fit in the screen (not be overscanned), but I didn't put much time into this.

Anyway, the way I got the full resolution was with a utility called SwitchRes X. This allows you to define custom resolution settings beyond those that OS X by default is willing to display, which many moderm Mac video cards will allow. Custom resolutions are quite complicated, with many parameters who's names or implications make little sense to me. Windows users have a utility called PowerStrip which serves the same purpose. It took a while to figure out how to come up with settings that had any chance of being valid. I've written a little SRX Helper-FAQ that explains what little I do know about making valid settings.

As for drving my Sharp LCD at it's native resolution, Here is what works. I would expect this to work equally for the LC-37GD6U, LC-37G4U, and possibly all Sharp LCD's who's native resolution is 1366x768. In particular, these values are probably specific to the Radeon 9200 that is build into my PowerBook, or possibly several of the Radeon series video cars. Note: Don't bother installing ATI's custom drivers. I did, and they didn't provide or enable any different capability.

* Pixel Clock and Scan Rate are intrinsically tied together and are a function of each other and the other values. My FAQ linked above explains as much as I understand about this. Simply put, you do not enter the Scan Rate values (even though the fields are editable). Rather, You enter Pixel Clock first, then all the other values - and both scan rates will be calculated for you.

Note that I'm sacrificing 6 pixels in horizontal resolution - this is the best I could get the OS and video card driver to accept (in other words, it's the closest value set I tried in SRX that actually showed up as selectable). For 6 pixels I was willing to declare victory.

Before you fine tune your TV, do the following on:
Select the DVI input (if you haven't already)
Menu->Setup->Input: Set it to 1366x768
View Mode: Select "dot by dot".

As I mentioned above, once you have the proper resolution, you have to calibrate your display to optimize its appearance. Initially it will probably be scaled slightly and flickering a little. The scaling will make certain types of imagery appear to have bands of varying color, where there should be a consistent color or pattern. If you tell your Sharp to Auto-Sync (Menu->Setup), and you've done the above settings first, it will probably get the resolution alignd correctly, but leave you with some flickering. I wrote up a detailed fine tuning post on the procedure I used to manually align the resolution, and remove the flickering. The test image I used for this procedure is attached.

I tried to attach the test pattern above, but it was rejected because it is 1280x768.

You really want the pattern to cover the entire screen so you can clearly see if there is any artifacting anywhere. So I've uu-encoded the file and loaded it as a text file. Stuffit (or WinZip) should be able to decode it fine, although you may have to strip the ".txt" off of the end.

Moderators - this file is only 4k as in 4000 bytes. Please don't reject it due to it's image size - the image size is necessary to fill a screen, because it is a test pattern.

Cool, I was wondering how that would work on a MAC. I'm very interested in the Mini Mac and it uses the same video card that you do. ATi doesn't limit resolutions settings to the values in the EDID like nVIDIA does but this is promising that it works on another platform.

Have you tried 1368x768? I used to use that on my old ATi Radeon 8500 on my WinXP machine. That would get you two pixels of overscan but at least you'd use up every pixel on the TV. :)

I am also very excited to hear about this. I currently have the EyeTV 200 hooked to an iMac G5. I love the feature set and performance of the 200 and recommend them to everyone. Customer service has been great. I just placed an order for an EyeTV 500 so I can record OTA HD and Clear QAM (local stations only) from our cable feed as well. (Too cheap to get the digital box + HD 'package', it's too expensive IMO.)

What I'm curious to know is whether the Mac Mini can drive the 37" Aquos well enough to play back analog and digital content from each of these boxes. The limited amount of VRAM (and no ability to upgrade it) concerns me. But if I knew it worked fine, I'd get one, put a 400 GB external FW drive on there and go to town. (The 250 GB internal drive on the iMac G5 is almost full, heh.)

I spoke with a guy from ElGato yesterday, and he said they hadn't received their Mac Minis yet to eval. However, he did state that they probably won't be able to drive HD, that's for sure. He mentioned the EyeHome wouldn't be able to support HD ever, either due to limited processing power. I am not very happy with my EyeHome, for many reasons, so that's why I'm looking at the Mini as my new HTPC.

That may be why they developed their Eyeconnect software. It's UPnP, it debuted at MacWorld SF2005, it's been tested so far with the D-Link and Streamium stuff, etc. It also will be a lot less processor intensive than the EyeHome software is, apparently. Public beta is sometime in February 2005, he said... in a few weeks. So I think that's where I'm going with this whole thing. Just waiting to see how the Mini 1.42 with at least 512 MB of RAM and an external drive will perform.

avramd, thanks so much for your work to date on this resolution issue. Do you have/use any EyeTV stuff? (I should also ask you to PM me and let me know where you got your Aquos, and for how much...)

VRAM is not an issue. The mini has more than enough VRAM to display 32 bit color simultaneously to a full 1920x1080. It has 32 MB, and that res/color depth takes barely 8 MB. I'm pretty sure extra video memory is only used for 2d/3d acceleration capabilities, and those are only used by software that explicity leverages the appropriate API. I'm pretty sure MPEG decoding doesn't touch it.

The limiting factor in playing HD is sheer processing power. My PB15 w/ 1.5 GHz G4 and PC2700 RAM is just about 5% too slow to decode 1080i mpeg2. Specifically, I used the Sharps' firewire output to record the series premeir of Point Pleasent in HD, over the air (using Apple's sample Virtual Digital VHS app ). It can record & replay the HD stream without skipping a beat (14% cpu). But to actually *decode* the stream and render it, it's pretty jumpy. My PB drives the Sharp magnificently. I'm going to get a mini too, to play back ripped DVD's, and to receive and play TiVo transfers once my TiVo's get upgraded with TiVo2Go capability.

As an update, I ended up getting the LC-37GD6U a few days ago. It's pretty sweet. I also received the EyeTV 500 today, so I'm excited to get that home and hooked up (hmm, maybe I'll be able to tune/record the Amazing Race finale... :) )

Anyway, I'm borrowing a Mac Mini to see how well it can show live TV, timeshifted, play stuff back and so forth. I'm still waiting for the DVI-I cable to come... then I'll be able to try out your settings for using it as a display.

In the meantime, avramd, I have a question: I tried connecting my PB15" 1.25 to the Aquos using a 6-to-4 pin firewire cable. I could use AVC Browser to see the model number and get info from the TV, but I could not play stuff back on the TV using the Virtual DVHS app. I haven't tried recording anything just yet.

I should probably bring this up in the "Firewire Recording" thread, but wondered if you had any luck with playback so far? All I get is the "No i.Link models found" message from the TV when I hit the i.Link button. Any ideas?

unithom, are you going to hook your Mac Mini up to the Sharp LCD? I have the same TV and want to hook a hard drive up to it for streaming music, Internet access, etc. I realize this is a little beneath what you guys are discussing, but I though the Mac Mini looked like it would work well for this purpose. THoughts?

The only thing you can possibly play back through the firewire cable is an HD mpeg2 stream that has been recorded, not necessarily by the D-VHS app, but I doubt you have anything else that will get such a stream to your disk.

So, you need to solve the device not showing up problem first. The order you connect things is significant, I think D-VHS has to be running before you connect the firewire cable, then you go to iLink on the TV. But I may have that backwards, it may be that firewire has to be connected before you launch D-VHS.

Anyway, yeah, there's a whole thread about this, I linked to it above.

I spent a few more bucks on the model with the tuner because it also had i.Link, and I wasn't sure whether the Mac Mini would be able to display HD resolution video natively.

However, so far I haven't been able to get Virtual DVHS to play anything back, I don't have my DVI-I cable yet to test on-screen playback from EyeTV recordings, I'm only borrowing a 1.25 Ghz and not a 1.42 model like I want, etc. Guess I just need to sit tight and wait!

The guys from ElGato said that they tried out the 1.25 on a monitor at 1280 and the output from the EyeTV 500 looked pretty good (OTA). So I have high hopes for this.

Some folks say there is pressure on Apple to open up an API for native video card MPEG playback functionality, and then the machine would be able to do quite a lot more video decoding on the fly. Right now it's all in software. There are other threads where people talk about using OpenGL for it but I'm not sure I completely follow their line of reasoning.

All I know is, I'm looking forward to future updates to see whether Tiger or Quicktime 7 or (whatever) opens up native access to hardware based (eg on the videocard) MPEG decoding.

Originally posted by PsycloneJackunithom, are you going to hook your Mac Mini up to the Sharp LCD? I have the same TV and want to hook a hard drive up to it for streaming music, Internet access, etc. I realize this is a little beneath what you guys are discussing, but I though the Mac Mini looked like it would work well for this purpose. THoughts?

PJ, I realized I forgot my traditional dig on the EyeHome. Originally I had this device (as you can see in my top picture from my setup schematic) but I was very disappointed by it. The remote control based interface for iTunes navigation was poor, same for the Photos, and web sites were kind of a joke too. It was mainly meant for playback of TV shows and movies you'd ripped to disk, but even those I had problems with. For one, you couldn't skip back/forward like you can with the EyeTV, and even trying to ffwd / rewind would sometimes cause the playback to just die. No easy way to get back to where you were, no display of what time was elapsed / remaining, etc. Even having two 100baseT hubs between the mac and the Eyehome caused such stutter that it was unbearable.

I realized that I'd been spoiled by apps like iTunes and iPhoto and Safari that 'just worked', at doing the things I wanted already. I love the EyeTV software and its functionality, so why not just put a Mac Mini in place of the EyeHome? Yes, it is more expensive. But with a bluetooth keyboard + mouse on my coffee table, PLUS the EyeTV remote, I have much more functionality than I did with just the EyeHome remote. So yes, this is going to be my HTPC and the 'media library', etc.

You Seem to be pretty good at this sort of thing, so I was hoping you could help me out.

I have the Sharp LC-32GD4U and I screwed up something and now my Mac Mini won't display on my TV with my DVI-D cable.

It was working fine before, but I was testing out different resolutions and I clicked on 1280x960. All of a sudden the signal went out. So I hooked the mini up to my monitor and changed the resolution to 1024x768 - the last working resolution i had it on. Now when I boot up my mini it says the 1024x768 @60Hz in the upper right hand corner, but after the boot process the moment where the user sign on screen is suppoesd to come up the signal cuts out and the TV says "Signal is not compatible with this input"!

I'm new to Macs... this is actually my first one, so I don't know what the problem is.

Originally posted by avramdThe only thing you can possibly play back through the firewire cable is an HD mpeg2 stream that has been recorded, not necessarily by the D-VHS app, but I doubt you have anything else that will get such a stream to your disk.

So, you need to solve the "device not showing up" problem first. The order you connect things is significant, I think D-VHS has to be running before you connect the firewire cable, then you go to iLink on the TV. But I may have that backwards, it may be that firewire has to be connected before you launch D-VHS.

Wow, that a relief. Thanks for your post, I tried it the other way around, DVHS running first, THEN plugging in firewire, and it finally 'took'! I was SO geeked to see the 'DVHS1' device finally show up in the i.Link list.

I followed a tip from the firewire forum and changed one of my EyeTV 500 recordings' mpg filename suffixes to .m2t, then I could play it with no difficulty using this app. Then I recorded something from off the TV onto disk and played it back as well.

At first I was NOT able to run the 500 MB LOTR clip, but on second try it also worked.

Hi everyone... I am considering buying one of the Sharp LCDs (32 or 37) and I DLd the manual and it says that it will only output limited video down the firewire line (eg no HDMI, DVI, Component etc)...

Is this true?

If yes then how does one get the stream to the mac? Getting a firewire STB isn't an option up here in Canada (sigh), so I was hoping to have the TV do it for me... methinks not...?

If you get a model with the built in tuner (eg it will have a 'D' in the model number, like LC-37GD4U instead of LC-37G4U) then it'll have firewire too.

If you tune something, like HD over the air, you can record it over firewire to the Mac using the Virtual DVHS application. That's because it's still in the encoded MPEG transport stream.

Stuff coming in via component, etc. aren't arriving as an MPEG stream, so it won't be sent from the firewire port. In other words, the TV doesn't encode MPEG from analog signals.

Therefore, depending on your playback source (what is it? cable? over the air? dish? etc) unless they offer firewire output, OR unless your TV can tune it (and output firewire itself) then you will be limited to recording an analog version of the signal, eg. using the EyeTV 200 or similar products.

A simpler way to think about it is this: If it is a High Definition source, then yes, the TV can output it over the firewire. It doesn't matter if it's cable high def or over-the-air high def, the answer is yes.

Technically I should have said "if it is a DTV source" b/c 480p counts too. I just didn't want to confuse people who don't understand that "digital cable" is not the same as "DTV."

The difference to keep in mind is this: If the TV's decoder is processing the digital signal, then it can also send a copy of that signal out the firewire port. If you have to set the TV to the actual channel you want to watch, and that channel has a decimal point in it, then it's digital. If you have to set the TV to analog chanel 3 or 4 so the cable box can decode, then the TV has no mpeg stream to copy to the firewire. Likewise if you're using composite, s-video or component, those are analog signals, so no dice. Finally if you're using HDMI or DVI input to the TV, they may be digital, but they are not MPEG2. There is no standard for sending a DVI signal over firewire, it wouldn't fit.

To elaborate, what I want to do is this, get a HD signal into the TV and send that signal out the firewire port.

I want hook up a mac and use the V-DVHS (I know this part works) for recording/playback... I know the mac isn't capable of HD mpeg2 decoding (g5s >>yes, Mac Minis>>no) so I want to send the mpeg2 stream back over firewire...

Ok, so I know all that works... here is the problem:

I live in Canada, and my cable provider uses the SA 3250 or 8300 boxes, but with the firewire disabled... worse still, they haven't rolled out Cablecards yet, and there is 1 (count 'em) HD OTA station in the city where I live...

What I was *hoping* to do was get the 3250 to output over DVI to the TV and send the signal down the firewire to the computer.

So I *think* I am sunk... but I have written the regulators to get the firewire ports activated... so we will see.

Would this work if I got an OTA source? What about CABLECard? Would I be able to output then?

THANKS again...

Now before everyone thinks that Canada must suck for TV, it is only my provider. There are other providers in other parts of the country that allow this, WITHOUT 5c flags! So you can see my motivation!

so yes, you can output the OTA HD source, but I think we've already covered that.

As for your cable company, it is possible that you don't need their box at all. I never ordered HD, I just put a splitter on the coax before plugging it into the analog antenna jack, and then plugged it also into the digital antenna jack as well. Then told the TV to go do it's channel discovery. There are a few different formats they can use, I tried them all, and the last one worked. I got 3 of the 5 HD channels they carry, all ones they pick up OTA themselves. The other two, Discovery and ESPN, I did not get. I don't know what's special about them or why my TV couldn't find them. I didn't spend much time looking into it.

Originally posted by avramdI got 3 of the 5 HD channels they carry, all ones they pick up OTA themselves. The other two, Discovery and ESPN, I did not get. I don't know what's special about them or why my TV couldn't find them. I didn't spend much time looking into it.

Because the OTA locals are sent in the clear and your QAM/ATSC tuner displays them. The others are encrypted.

Yeah, the cable provider up here uses 256 QAM, so I am SOL I NEED a box... sigh.

Well, thanks for everyone's help!

So, anyone with a CABLECARD? Will that allow output over the iLink?

If that works, in the worse case, I will just wait for CABLECard, lots of TVs up here are comming equiped with slots for them, so I think the local cable co will have to support them sooner or later :(

Thanks again everyone.

Back to something a little more "on topic"... how does the Mac look on the Sharps? I would think that getting the "native" resolution is key?

I tried using your settings in SwitchResX but no dice. I have done so on both the Mac Mini 1.25 ghz (the 9200) and the Powerbook 15" fw800 (9700).

When I try to input certain settings, as soon as I leave the box, they change on me!
So for example, when I enter 'front porch' of 130, it changes to 128. A value of 132 stays put. When I try 114, it becomes 112.

In DisplayConfigX, I am unable to put zeros for the numbers on the right, they all change to ones.

I simply have a hard time believing that a reboot is actually necessary to truly implement these resolutions, fwiw. There has got to be a way to force the Mac OS to stick new resolutions in the list of ones it'll try. Then you could just pick that new custom res, if it doesn't work, hit esc, etc.

I'm also really frustrated by the fact that it wants to make the Sharp be Monitor #1, with the menu bar. I have to go into the other room, fire up Remote Desktop, etc. I wish there were an assignable hotkey that'd switch menubar locations. Maybe I can map something to run cscreen. (Which ITSELF doesn't seem configurable to 'force' a new resolution, either! Grargh!)

When I had the Mac Mini (I borrowed one for a short time), I was more successful -- but only briefly. It booted into a good resolution, or at least I think so-- hard to tell, didn't run any tests -- but when I switched inputs on the Sharp, eg to component, then switched back later, it was all fuzzy and weird. It was almost like it started out as a digital signal, then went analog on me later... and screwed up, to boot.

Pulling my hair out. I know there has to be a better way.

avramd, based on your step by step guide -- if someone such as yourself has already done the math for this display, then why should the settings be ANY different for anyone else? Because of different display cards?

I'm sorry you're having so much trouble - believe me, it was just as frustrating for me.

Yes, the difference in the display cards would explain why one would work but not another.

As for the changing values, it could be that SRX is forcing your values to be divisible by 4. SRX does that with the resolution itself, but I didn't think it did it with all of the other timings. I'm actually running a one-off version of the SRX control that doesn't do that, to test it for the author. I think he plans on including it in a future update. However, I wouldn't expect a difference of 2 pixels to be a deal breaker.

One thing you have to keep reminding yourself of is that you can get 1280x768 without all of this custom resolution frustration, and it is only 80 pixels narrower than if you do get all this to work. I told myself over & over again to let it go & stop wasting my time, but somehow I couldn't let it go.

As for modifying the menu, the author of SRX told me that in some cases just logging out & logging back in is good enough. The trouble is that there are only certain times when OS X reads the file, and the author hasn't found a way to force it to do so. Yes, it's frustrating.

That main display thing happened with me too, I never did figure it out. You're doing this with a power book though, right? You can switch all of this stuff with the context-menu; control-click on the desktop on either display, and you get sub-menus that can change resolutions on either one, and switch the menu bar. As long as you have one working display, you shouldn't need to remote in.

I also did have a case of a resolution working, and then failing to work later; 1344x756 which is what the HDMI input negotiates. I tried it on the DVI and it worked. But at some point it stopped working, and I never did get it back. But that is partly b/c when I got 1360x768 working, I stopped trying for the others.

As before, scan rates are computed for you, you don't set them. See the rest of the thread regarding my procedure for how to fine-tune your display for optimum picture synchronization (pixel alignment, scaling avoidance, and flicker reduction).

Hi,
I read your posting and hope you can help. I have a Dual 2.5 GHz G5 and want to use the DVI input on my Sharp LC-32GD4U but every time I boot up with it plugged in, the TV displays "The signal is not compatible" or something to that effect. I have a Dr. Bot DVI Extractor which connects to the ADC connector and allows for a regular DVI monitor to work. I plugged in a regular 19" Planar LCD screen into it then plugged the Sharp into the DVI port of my G5. With the Planar attached I get video on my Sharp. I set the resolution to 1280 x 768 at 60Hz and it looks fabulous however, when I unplug the Planar and restart, I get that same error message. It seems that without another monitor plugged in the Mac does not send it the right resolution. The strange thing is that I have a PC running XP Pro and it works fine on that computer. Someone PLEASE HELP! Thanks.

Great Post! I just got a Mac Mini as well and I'm trying to get rid of the overscanning issue on my 62" Toshiba DLP (62HM84). I tried using SwitchRes X to change it but didn't have any luck with it, as I didn't know how to input the custom settings. I read your help file on it and I am still a little unsure and I do not want to end up with the Dreaded "Signal Not Compatible" Message.

Could you suggest some settings for me to try with my 62" Toshiba DLP (Model 62HM84)? I have the Mac Mini 1.42 with 1 Gig of Ram 80 Gig HD. I'm connecting from DVI to HDMI on the DLP.

I think I may give your latest settings a try and see what comes of it as well. But since you understand the SwitchRes X rather well, I was hoping maybe you could give me a couple Settings to try with my DLP Set.

It's not knowledge of SRX that you need, it is knowledge of working values for your existing setup. You need to find out what settings the built-in resolutions are using, and then tweak from there, by adjusting front & back porch, etc, to tune out the overscan issue.

However, there is no simple answer for how to find out what the existing settings are. I believe the author of SRX has developed the ability to show you the values of existing resolutions, but AFAIK, he hasn't included it in a public version of his product yet. I highly recommend you email him and ask when he plans to do that, and if he'd be willing to let you try a development version with that functionality.

In theory, you could develop custom settings from scratch, but you would need to know a LOT more about display technology than I do, and you would probably also need detailed internal specifications of both your TV and your video card, neither of which are likely to be publicly available.